docs: def dataframe(self):
          """
          Returns a pandas DataFrame containing all other class properties and
          values. The index for the DataFrame is the string URI that is used to
          instantiate the class, such as '201806070VEG'.
          """
          if self._away_goals is None and self._home_goals is None:
              return None
          fields_to_include = {
              'arena': self.arena,
              'attendance': self.attendance,
              'away_assists': self.away_assists,
              'away_even_strength_assists': self.away_even_strength_assists,
              'away_even_strength_goals': self.away_even_strength_goals,
              'away_game_winning_goals': self.away_game_winning_goals,
              'away_goals': self.away_goals,
              'away_penalties_in_minutes': self.away_penalties_in_minutes,
              'away_points': self.away_points,
              'away_power_play_assists': self.away_power_play_assists,
              'away_power_play_goals': self.away_power_play_goals,
              'away_save_percentage': self.away_save_percentage,
              'away_saves': self.away_saves,
              'away_shooting_percentage': self.away_shooting_percentage,
              'away_short_handed_assists': self.away_short_handed_assists,
              'away_short_handed_goals': self.away_short_handed_goals,
              'away_shots_on_goal': self.away_shots_on_goal,
              'away_shutout': self.away_shutout,
              'date': self.date,
              'duration': self.duration,
              'home_assists': self.home_assists,
              'home_even_strength_assists': self.home_even_strength_assists,
              'home_even_strength_goals': self.home_even_strength_goals,
              'home_game_winning_goals': self.home_game_winning_goals,
              'home_goals': self.home_goals,
              'home_penalties_in_minutes': self.home_penalties_in_minutes,
              'home_points': self.home_points,
              'home_power_play_assists': self.home_power_play_assists,
              'home_power_play_goals': self.home_power_play_goals,
              'home_save_percentage': self.home_save_percentage,
              'home_saves': self.home_saves,
              'home_shooting_percentage': self.home_shooting_percentage,
              'home_short_handed_assists': self.home_short_handed_assists,
              'home_short_handed_goals': self.home_short_handed_goals,
              'home_shots_on_goal': self.home_shots_on_goal,
              'home_shutout': self.home_shutout,
              'losing_abbr': self.losing_abbr,
              'losing_name': self.losing_name,
              'time': self.time,
              'winner': self.winner,
              'winning_abbr': self.winning_abbr,
              'winning_name': self.winning_name
          }
          return pd.DataFrame([fields_to_include], index=[self._uri])